[Spinal ataxia caused by an occipito-atlanto-axial malformation in a lamb]

A three month old lamb suffering from locomotory disturbances was submitted to the clinic. It had a tilted head to the left and an atactic gait especially in the hind limbs. When it was forced to stop or to change direction it fell down. General condition and sensorium were apart from a reduced bathyaesthesia normal. By clinical and laboratory examination some possible causes of locomotion disturbances in lambs like copper deficiency, nutritive muscle dystrophy and meningitis could be ruled out. By X-ray examination an asymmetry of the os occipitale and atlas was diagnosed. They were not well distinguishable from each other. The second vertebra showed a rotation with angulation of its longitudinal axis to the left and a dorso-lateral subluxation. By myelography a narrowing of the vertebral canal between first and second vertebra could be shown. Because of the poor prognosis the animal was euthanised. The pathological examination confirmed and completed the X-ray findings.